Analog radio over fiber (AROF) is increasingly seen as a viable alternative to conventional digital optical transmission, e.g., the common public radio interface (CPRI), for the next generation wireless systems to directly transmit the analog signal to the antenna. A simple optical detector at the antenna-top converts the analog optical signal into analog electrical signal, to be amplified with a radio frequency (RF) power amplifier (PA) and transmitted into the free space, thereby reducing the complexity of requiring digital to analog conversion circuitry at the antenna top. This methodology, however, puts stringent demands on the optical link in terms of linearity, noise and crosstalk. One such important system parameter dependent on a combination of system linearity, noise and crosstalk is adjacent channel leakage ratio (ACLR). ACLR is defined by the international committee on 3GPP as the ratio of the integrated power in the adjacent channel to the integrated power in the channel of interest.
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